I have 4 SLWs since they were a couple days old. 2 were female, 2 were male. Seemed like it took a couple months before it was definitely discernable which ones were male. I think it was just the anxiety of not being able to sex them like a sex-link breed. I agree with everyone else who responded, your photos all look like roosters. At 16 weeks mine seemed to develop more noticeable tail feathers as compared to the females, who had no special plumage at the tail at the same age. #4 looks like his tail feathers are just starting to stick up, but he has hackles already. Same with the comb and wattles. The roos also got heavier faster than the girls did. You should soon see the males stand much taller. Mine weren't in a hurry to crow, but when they started, they never stopped. They are beautiful birds though. They get a lot of attention when they are strutting around.